* {
    margin: 0;
    padding: 0;
}

.box {
    position: relative;
    width: 400px;
    height: 600px;
    margin: 100px auto;
    background-color: skyblue;
}

.cloud {
    position: absolute;
    left: 50px;
    top: 200px;
    width: 70px;
    height: 70px;
    border-radius: 50%;
    background-color: white;
    box-shadow: 40px -40px 0 10px #fff,
    90px -5px 0 2px #fff,
    40px 10px 0 #fff,
    120px 0 0 -5px #fff;
}